1. Field of the Invention
The present invention relates to a rear projection type display apparatus and method for an automotive vehicle in which a field of view can arbitrarily be controlled.
2. Description of the Related Art
A Japanese Patent Application First Publication No. Heisei 1-248885 published on Oct. 4, 1989 (which corresponds to a U.S. Pat. No. 5,059,957 issued on Oct. 22, 1991) exemplifies a previously proposed display apparatus for the automotive vehicle.
In the previously proposed display apparatus disclosed in the above-described Japanese Patent Application First Publication, a liquid crystal filter is installed on a display screen as means for controlling a field of view in the display apparatus. A characteristic of the liquid crystal filter is varied so as to achieve such a technique as limiting a display for a vehicular driver during a vehicular run.
However, if the characteristic of the liquid crystal filter is varied, a transmittance of a whole display screen is reduced and even the information to be displayed becomes unclear.
In addition, a louver filter used in the limitation of a field of view limits, in general, fixedly a predetermined field of view. Hence, it is impossible to control arbitrarily a timing of the limitation of the field of view or to control arbitrarily the field of view limitation in a direction different from each region of a displayed image.
It is, hence, an object of the present invention to provide display apparatus and method which are capable of arbitrarily controlling a field of view region of a display and a timing of the display, while maintaining a clear display of a display image.
The above-described object can achieved by providing a display apparatus comprising: a projecting section that projects a display image; a first screen enabled to switch its state between a light transmission state in which the projected display image is transmitted therethrough and a light diffusion state in which the projected display image is projected thereon; a second screen enabled to switch its state between the light transmission state and the light diffusion state; a field of view limiting section interposed between the first screen and second screen to limit a field of view of a predetermined direction; and a controlling section that controllably switches the respective states of the first and second screens.
The above-described object can also be achieved by providing a display method comprising: projecting a display image; providing a first screen enabled to switch its state between a light transmission state in which the projected display image is transmitted therethrough and a light diffusion state in which the projected display image is projected thereon; providing a second screen enabled to switch its state between the light transmission state and the light diffusion state; providing a field of view limiting section interposed between the first screen and second screen to limit a field of view of a predetermined direction; and controllably switching the respective states of the first and second screens.
This summary of the invention does not necessarily describe all necessary features so that the invention may also be a sub-combination of these described features.